System for damping and distributing the stress exerted on the human body during an emergency ejection procedure by means of an ejector seat

ABSTRACT

A device for protection of a spinal column of a pilot during an ejection shock comprises an ejectable seat with a seat back having tensioners integrated therein, a rigid framework and a buttock support. To prevent concentration of the weight of the upper portion of the body on the lumbar/abdominal region, the buttock support is lowered through use of an electromagnetic arrangement retracting connection elements between the seat back and the rigid framework.

BACKGROUND OF THE INVENTION

The present invention relates to the use of an emergency ejectionprocedure by airplane pilots or other crew members immediately upon theneed arising for ejection from their aircraft. More particularly, theejector seat with a standard sub-vertical inclination of this inventionpreserves the integrity of the pilot's body at the moment of ejectionand reduces or even eliminates any risk of consequential physicalafter-effects and thus, in a hostile zone of operation, increases thepilot's ability to survive.

In the past and conventionally, a pilot was ejected from an aircraft byfiring an explosive device situated beneath the center of a seat havinga rigid framework, thereby transferring the thrust of the kinetic loadof the explosion to the spinal column and rib cage with the consequentrisk of serious trauma to various internal organs and the surroundingmuscular skeletal structure.

To a large extent, the invention disclosed hereby remedies this severedrawback.

SUMMARY OF THE INVENTION

In this disclosure, the application of the kinetic force and the forcesof acceleration caused thereby is altered so that it is exertedindependently on the thoracic region (the trunk) and on the abdominalregion, thereby dividing the forces applied to the body substantially inhalf, as follows:

1) first, the trunk of the pilot is placed under tension by a harnessthereabout placing the trunk into a sub-vertical traction;

2) second, the buttock support is dropped relative thereto, in acontrolled manner. Given the basic structure of the spinal column, theseat can not be dropped more than a few centimeters. While this isnecessary, it is at the risk of losing some of the effectiveness of thetension locking on the trunk because of natural or accidental slack. Ifthe slack between the seat back and the pilot's were to amount toseveral centimeters, such slack would defeat the desired objective ofdistributing stresses. The dropping of the support must be activatedimmediately before or simultaneously with the firing of the emergencyejection system.

3) Simultaneous and complementary actuation of the above is essentialand constitutes the third fundamental characteristic of the invention.

Thus, immediately prior to ejection, the buttock support of the seat isreleased and drops in passive, but controlled manner, while the trunk ofthe pilot is placed under traction against the top of the seat back.Thus, the trunk is suspended for a very short length of time beforethrust of the ejection system is applied to the bottom portion of thebody.

This device distributes the kinetic forces of ejection between thethoracic and the abdominal regions. In contradistinction thereto priorart systems, in spite of the pilot's back being forced against the seatback, this distribution of kinetic forces is not achieved and the loadis essentially concentrated on the bottom portion of the spinal column.This is not improved by the interposing of "airbag" systems and othersurvival equipment.

Here, unlike the prior art single thrust effect, the present inventionprovides a "push-pull" effect. Thereby very significantly reducing thechance of injury by substantially halving the mass which is subjected toacceleration and related forces.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following drawings, the same parts in the various views areafforded the same reference designators.

FIG. 1 is a schematic view of the pilot's body in relation to theemergency ejection apparatus of the present invention;

FIG. 2 is a partial schematic view of the emergency ejection apparatusof the present invention shown in FIG. 1;

FIG. 3 is a schematic view of the harness of the emergency ejectionapparatus of the present invention shown in relation to the pilot'sbody;

FIG. 4 is a schematic view of the buttock-supporting mechanism for theemergency ejection apparatus of the present invention, said mechanismshown in the flight position;

FIG. 5 is a schematic view similar to FIG. 4, but shown during theejection procedure;

FIG. 6 is a schematic view of a second embodiment of thebuttock-supporting mechanism shown in FIG. 4 and is shown in the flightposition; and,

FIG. 7 is a schematic view similar to FIG. 6 but shown during theejection procedure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the present disclosure, the emergency ejection procedure thereofessentially begins by initiating a signal that electronically actuates atensioner thereby locking the coupling between the pilot's trunk and theback of the ejectable seat and placing the pilot's trunk inupwardly-directed tension. Although the order to actuate the tensionerprecedes by a short time interval the order to fire the emergencyejection unit, the order to release the seat must be independent fromthose two sequences.

Referring now to FIGS. 1 through 5, the first embodiment is described.In FIG. 1, the manner in which the forces are distributed between theupper portion of the body (1), i.e. the head and the chest, and thelower portion (2) thereof, i.e. the abdomen is shown. This isaccomplished by activating harness or flying suit tensioner(s) (3)integrated in the seat back, thereby partially suspending the upperportion of the pilot's body. The force distribution occurs, uponejection being initiated, in that the suspension of the upper portion isby an amount of the same order of magnitude as the pilot's body weight,and further upon being subjected to ejection thrust (25), by the limiteddropping (4) of the support for the pilot's buttocks within the generalframework (5) of the ejectable seat.

FIG. 2 shows the principle constituents of a system for partiallysupporting the pilot. The main elements thereof are the top (6) of theejectable seat, a microprocessor (7) for controlling the ejectionprocedure, structural or add-on tensioners (3) that are electronicallylocked, and that are connected via a belt (8) and an open loop (9) tobraces (10) connected beneath the pilot's armpits. Under a zero loadfactor, the tensioner locks upon experiencing a traction force of about15 kilograms.

The harness, FIG. 3, for the emergency ejection system is used as shownbeneath the armpits. While, in this case, the harness (11) is designedas a separate harness that is in addition to the standard pilot'sharness, it is understood that the harness could also be designedintegrally therewith. The a harness (11) for the trunk comprises tubularcomponents (11a) providing a total airbag function for the thoracicregion and is constructed to be worn about the trunk and beneath thearmpits. The harness (11) is connected via straps (10) and engages afree coupling (9) with two seat-top tensioners. The harness (11) isconstructed to include an orthopedic foam neck or airbag-effect collar(12), optionally removable, with the right and left main portionsthereof being assembled together via a chest fastening (13).Alternatively the tension locking for the harness beneath the armpits isinstallable directly under the flying suit and over the pilot's trunk.

In FIG. 4 the profile of a static stylized device of the firstembodiment is shown. The device has the following component elements:the seat back (14) and the bucket (15, 16, 17). These components,forming the rigid framework of the ejectable seat, enable by a pivotingaction along the front axis (18) to drop the pilot's buttock-support(4). The dropping action is effectuated by retracting symmetricalretractable studs (19, 20). The drop is quickly limited and controlledby a coil spring (21) mounted on pivots (22, 23), which spring assemblyis embedded in a block of foam (24) of a density that increases goingdownwards. The spring/foam damping assembly provides progressiveresistance to the load from the bottom portion of the pilot's bodydownwards to a bottom abutment position. The bottom abutment position isapproximately within 10 centimeters of the initial static position. Thebuttock support drop described herein may be damped by many other means,the spring/foam combination is merely one possibility amongst others,and is not limiting or exclusive.

In operation and during an ejection sequence, the studs (19 and 20),FIG. 5, are retracted under the effect of the ejection thrust field(25). Thereupon, as the studs retract, the buttock support (4) pivotsand provides the requisite drop.

Referring now to FIGS. 6 and 7 a second embodiment is shown. In FIG. 6the profile view of the static device of the second embodiment is shown.This embodiment provides for the entire pilot's buttock support to dropin a controlled manner. The device has the following components: seatframework elements (14, 15, 16, 17), a buttock support (4) resting onretractable studs (19, 20), which studs are locked electromagneticallyor otherwise. A helical spring (21) is attached by fixed or pivotingmeans (22, 23) between buttock support (4) and framework element (16).Similar to the first embodiment, the spring is embedded in a block (24)of foam of density that increases going downwards. As in the firstembodiment, the dropping of the buttock support can be controlled bymeans of any other system or technique for absorbing motion, with thetechnique proposed not being limiting.

In operation and during an imposition of an ejection force (25), FIG. 7,after the studs (19, 20) retract, a portion of the weight of the pilotis supported by the device.

The system optionally includes guide rails along edges (15, 17) of theseat bucket and symmetrical rails behind them. As in the firstembodiment (FIGS. 4 and 5), the buttock support abutment is provided bythe spring/foam assembly.

The figures are schematic in form. The extent to which the buttocksupport drops has, as indicated above, been approximated. The additionaldegree of freedom given to the abdominal portion of the pilot's bodyrelative to possible displacement of the thoracic portion thereof hasbeen approximated to be in the range not greater than 10 centimeters. Itis theorized that, if the traction anchoring between the seat back andthe pilot's trunk were perfect, i.e. with no give, as provided byadjusting the tensioner as a function of the top portion of the pilot'sbody (FIG. 1), then it would not be necessary to provide assistance froma second device for separating masses. However, the achievement of thisoptimum condition is highly unlikely because the lack of stiffness inthe harness and of the flying suit. Thus to compensate therefor the seatproper is made to be movable.

It is thus possible to analyze as above the two fundamentalmodifications proposed by the invention on initiation of the ejectionprocedure to achieve the following objectives:

a) suspending the top portion of the pilot's body (FIG. 1) byelectronically activating tensioners (FIG. 3 at 7) as a function of theload factor to which the body is subjected, stiffening the entireharness upwards (FIG. 2 at 8 and 10, and FIG. 10 at 11) and applyingpressure to an airbag corset beneath the armpits (FIG. 3 at 11a); and

b) releasing the buttock support in controlled manner by retracting itsfixing points (FIGS. 4 and 5 at 19 and 20) and (FIGS. 6 and 7).

The above thus serve to dissociate the mass of the spinal column and ribcage into two regions: the thoracic and the the armpits (FIG. 3 at 11a);and

b) releasing the buttock support in controlled manner by retracting itsfixing points (FIGS. 4 and 5 at 19 and 20) and (FIGS. 6 and 7).

The above thus serve to dissociate the mass of the spinal column and ribcage into two regions: the thoracic and the abdominal region, each ofwhich is half as heavy for given acceleration. The acceleration can thanbe withstood without damage.

While the accompanying drawings below show the invention in the form oftwo embodiments for retracting the buttock support, such embodiments arenot limiting in any way. Further, variants of the harness device (notshown herein) can be designed by modifying a standard harness, whilenevertheless eliminating any functional linkage with the connections forthe pelvis belt and the size of the pilot, or by integrating the armpithardness as described above with the flying suit.

What is claimed is:
 1. A device for protection of a spinal column of apilot during an ejection shock, comprising:an ejectable seat with a seatback having tensioners integrated therein, a rigid framework and abuttock support, said tensioners being activated by a microprocessorinitiating the ejection procedure, action of said tensioners beinglimited in time and said tensioners relieving a lumbar/abdominal regionof a body of a pilot by placing an upper part of a pilot's chest undercontrolled forces in the direction of an ejection thrust, said forcesbeing directed from a bottom portion toward a top portion of the seatand providing controlled lowering of the buttock support in the oppositedirection; and to prevent concentration of the weight of the upperportion of the body on the lumbar/abdominal region, the buttock supportis lowered through use of an electromagnetic arrangement retractingconnection elements between the seat back and the rigid framework;whereby the inertia of the ejected mass being substantially reducedsuppressing risk of a spinal column trauma.
 2. The device according toclaim 1, wherein said tensioners consist of a harness situated underarmpits of the pilot.
 3. The device according to claim 2, wherein saidharness is an airbag harness.
 4. The device according to claim 2,wherein said tensioners include a passive or airbag orthopedic neckcollar combined with a chest harness.
 5. The device according to claim4, wherein said chest harness comprises braces, an open loop for rapidconnection between said tensioners and a harness braces, said loophaving two converging but independent complementary curved ends providedto facilitate connection and disconnection of said harness.
 6. Thedevice according to claim 2, further comprising spring and foam shockabsorbing means which operates between a position having substantiallyminimal resistance and an abutment position during the lowering of thebuttock support.
 7. A device for protection of a spinal column of apilot during an ejection shock, comprising:and ejectable seat forreceiving a body of a pilot, said seat having a rigid framework, thepilot being retained with the seat by a chest harness; a microprocessorfor initiating the ejection procedure of said ejectable seat; said seatcomprising a seat back and tensioner means integrated in said seat back,said tensioner means being activated by said microprocessor, action ofsaid tensioner means being limited in time, said tensioner means whenactivated relieving a lumbar/abdominal region of said body by placing achest of the pilot under controlled forces in the direction of anejection thrust, said forces being directed from a bottom portion towarda top portion of the seat, and said seat further comprising a buttocksupport mounted on said framework to be movable in the directionopposite to the direction of the ejection thrust from a buttocksupporting position to a buttock releasing position, restraining meansfor holding said buttock support in said buttock supporting position andmeans activated by said microprocessor for releasing said restrainingmeans and for controlled lowering said buttock support from said buttocksupporting position to said buttock releasing position, whereby todiminish a risk of a spinal column trauma and to avoid concentration ofthe weight of the upper portion of said body on the lumbar/abdominalregion thereof during the ejection, the inertia of the ejected massbeing substantially reduced.
 8. The device according to claim 7, whereinsaid tensioner means comprises a harness situated under armpits of thepilot.
 9. The device according to claim 8, wherein said harness is anairbag harness.
 10. The device according to claim 7, wherein saidtensioners include a passive or airbag orthopedic neck collar combinedwith said chest harness.
 11. The device according to claim 7, whereinsaid chest harness comprises braces, an open loop for rapid connectionbetween said tensioner means and said harness braces, said loop havingtwo converging but independent complementary curved ends provided tofacilitate connection and disconnection of said harness.
 12. The deviceaccording to claim 7, further comprising spring and foam shock absorbingmeans which operates between a position having substantially minimalresistance and an abutment position during the lowering of the buttocksupport.